Personal audio devices, including wireless telephones, such as mobile/cellular telephones, cordless telephones, mp3 players, and other consumer audio devices, are in widespread use. Such personal audio devices may include circuitry for driving a pair of headphones or one or more speakers. Such circuitry often includes a speaker driver including a power amplifier for driving an audio output signal to headphones or speakers. Oftentimes, a power converter may be used to provide a supply voltage to a power amplifier in order to amplify a signal driven to speakers, headphones, or other transducers. A switching power converter is a type of electronic circuit that converts a source of power from one direct current (DC) voltage level to another DC voltage level. Examples of such switching DC-DC converters include but are not limited to a boost converter, a buck converter, a buck-boost converter, an inverting buck-boost converter, and other types of switching DC-DC converters. Thus, using a power converter, a DC voltage such as that provided by a battery may be converted to another DC voltage used to power the power amplifier.
Battery-powered systems may use a boost converter to generate a power supply for an audio amplifier that is greater than a voltage of the battery. For example, a motivation of using a boost converter in a battery-powered audio system is to generate a higher sound pressure level by allowing a greater signal swing at the output of an audio amplifier than could be achieved by powering the amplifier directly from the battery. However, using a boost converter to achieve a boosted voltage may be problematic in portable electronics applications due to the physical size of an inductor required to provide such boost which may render implementing a boost converter with a single stage to be an unattractive option.